I have only seen boxed Athena kits offered for HUGE sums of $$.
Carl at Semroc sent me a prototype of a SLS Enerjet Athena kit many years ago. Only one in existence, so it's rarer than even original kits. He never found a source for the plastic wraps, so was never kitted.
Won't be built.

I have at least seen Athena kits offered. Your visible Astro was the only one of those seen by me.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !